Disc drive systems are well-known. They include data heads including transducer elements for reading or writing data to a recordable disc. Transducer elements of the data heads are electrically coupled to the main drive circuitry through a head interconnect circuit. Conductive paths on the head interconnect circuit electrically couple head leads coupled to transducer elements on the head to circuit leads connected to drive circuitry.
Heads are supported relative to a disc surface by a head actuator. A drive circuit is mounted on the head actuator and circuit leads on the head interconnect circuit are coupled to lead connectors or solder pads on the drive circuit via a flex on suspension (FOS) circuit. Leads are supported along an edge of a lead tip of the head interconnect circuit and connectors or solder pads are aligned along a slot or edge of the drive circuit. The lead tip is inserted into the slot or aligned with the edge to couple the circuit leads to connectors. Leads are soldered to connectors to electrically connect transducer elements of the head to main drive circuitry.
Prior to soldering, leads are aligned with the connectors or solder pads to assure desired electroconnection for read and write operations. Drive circuits on a head actuator include a conductive metal substrate supporting a printed circuit. During the soldering operation, solder can wick from the solder pad or connector to surrounding features. Solder that wicks to a metal substrate can short the electroconnection between the data heads and drive circuitry making the data heads defective. Similarly, solder can bridge from the solder pads to the shunt bar. The shunt bar is removed from the FOS circuit during assembly and after the flying leads are soldered to the solder pads. If solder attaches to the shunt bar, extra force is required to remove it. This can result in the surface of the printed circuit delaminating and result in a defective circuit. The present invention addresses these and other problems, and offers other advantages over the prior art.